1. Technical Field of the Invention
The invention relates generally to methods and devices for coupling a device to a surrounding mating part. More specifically, the invention relates to coupling methods and devices that provide high rates of thermal transfer, good anti-rotation characteristics, and/or shielding against electromagnetic interference.
2. Background of the Related Art
One perennial problem in design and configuration of electromechanical systems is removal of excess heat created during operation of electromechanical devices, such as motors, batteries, and electronics units. It is desirable that heat produced by such devices be conveyed to surrounding housings or other heat sinks. A difficulty in conveying the heat from the heat-producing electromechanical devices to the surrounding heat sinks has been conveying the heat across a gap between the device and the heat sink. One prior attempt at solving this problem has been to provide tightly toleranced mating surfaces between the heat-producing device and the surrounding heat sink or housing, so as to minimize the air gaps between the heat source and the mating part. It will be appreciated that tight tolerances may be difficult to successfully manufacture, and in any case, may increase manufacturing costs and complexity. Also, even small air gaps may involve a large thermal resistance, due to the low thermal conductivity of air.
Another approach has been to place a thermal grease into the gap between the electromechanical heat source, and the mating part. Such a thermal grease has the advantage of having a much higher thermal conductivity then air, thereby making for a low thermal resistance between the heat source and the mating part. Such thermal greases typically are petroleum-based materials, with metallic particles therein, for increased thermal conductivity. However, such thermal greases have the drawback of being viscous, and difficult to place only in the gap. When the thermal grease gets into an undesired area, it can be very difficult to clean.
From the foregoing it will be appreciated that there is room for improvement in the general field of thermal transfer between heat-producing devices and mating parts.